{#- ===== SECTION 1: MACRO render_content =====
     Handles string, list (image/video/text items), or None/undefined.
     count_vision=true: increments ns.image_count / ns.video_count.
-#}
{%- macro render_content(content, count_vision=false) -%}
  {%- if content is string -%}
    {{- content -}}
  {%- elif content is iterable and content is not mapping -%}
    {%- for item in content -%}
      {%- if item.type == 'image' or 'image' in item or 'image_url' in item -%}
        {%- if count_vision -%}{%- set ns.image_count = ns.image_count + 1 -%}{%- endif -%}
        {%- if add_vision_id is defined and add_vision_id -%}
          {{- 'Picture ' ~ ns.image_count ~ ': ' -}}
        {%- endif -%}
        {{- '<|vision_start|><|image_pad|><|vision_end|>' -}}
      {%- elif item.type == 'video' or 'video' in item -%}
        {%- if count_vision -%}{%- set ns.video_count = ns.video_count + 1 -%}{%- endif -%}
        {%- if add_vision_id is defined and add_vision_id -%}
          {{- 'Video ' ~ ns.video_count ~ ': ' -}}
        {%- endif -%}
        {{- '<|vision_start|><|video_pad|><|vision_end|>' -}}
      {%- elif item.type == 'text' or 'text' in item -%}
        {{- item.text -}}
      {%- endif -%}
    {%- endfor -%}
  {%- endif -%}
{%- endmacro -%}

{#- ===== SECTION 2: NAMESPACE INITIALISATION =====
     Single ns object for all mutable state.
     enable_thinking  default=true  (BUG-003 fix)
     preserve_thinking default=true: when false, suppresses think-block output in
                       generation prompt and overrides enable_thinking to false.
                       Passed via --chat-template-kwargs {"preserve_thinking":false}.
-#}
{%- set ns = namespace(
    enable_thinking=true,
    image_count=0,
    video_count=0
) -%}

{#- Resolve enable_thinking kwarg -#}
{%- if enable_thinking is defined -%}
  {%- if enable_thinking -%}
    {%- set ns.enable_thinking = true -%}
  {%- else -%}
    {%- set ns.enable_thinking = false -%}
  {%- endif -%}
{%- endif -%}

{#- Resolve preserve_thinking kwarg.
    preserve_thinking=false  => force non-thinking mode (same as enable_thinking=false).
    preserve_thinking=true   => default, no override (thinking controlled by enable_thinking).
    When not defined         => default, no override.
-#}
{%- if preserve_thinking is defined and not preserve_thinking -%}
  {%- set ns.enable_thinking = false -%}
{%- endif -%}

{#- ===== SECTION 3: PRE-SCAN =====
     Track last /no_think or /think flag in user messages.
     Also scan system messages for <|think_off|> / <|think_on|> markers
     (allows apps to control thinking mode via system prompt injection).
     The model follows the last flag encountered in multi-turn conversations.
-#}
{%- for i in range(messages | length) -%}
  {%- set _msg = messages[i] -%}
  {%- if _msg.role == 'user' -%}
    {%- set _u = _msg.content if _msg.content is string else '' -%}
    {%- if _u.rstrip().endswith('/no_think') -%}
      {%- set ns.enable_thinking = false -%}
    {%- elif _u.rstrip().endswith('/think') -%}
      {%- set ns.enable_thinking = true -%}
    {%- endif -%}
  {%- elif _msg.role == 'system' or _msg.role == 'developer' -%}
    {%- set _s = _msg.content if _msg.content is string else '' -%}
    {%- if '<|think_off|>' in _s -%}
      {%- set ns.enable_thinking = false -%}
    {%- elif '<|think_on|>' in _s -%}
      {%- set ns.enable_thinking = true -%}
    {%- endif -%}
  {%- endif -%}
{%- endfor -%}

{#- ===== SECTION 4: COLLECT SYSTEM CONTENT =====
     Merge all system/developer messages with \n\n separator (BUG-004 fix).
     <|think_off|> / <|think_on|> markers are stripped from output.
-#}
{%- set ns_sys = namespace(content='') -%}
{%- for msg in messages -%}
  {%- if msg.role == 'system' or msg.role == 'developer' -%}
    {%- set _c = render_content(msg.content | default('')) | trim -%}
    {%- set _c = _c | replace('<|think_off|>', '') | replace('<|think_on|>', '') | trim -%}
    {%- if _c -%}
      {%- if ns_sys.content == '' -%}
        {%- set ns_sys.content = _c -%}
      {%- else -%}
        {%- set ns_sys.content = ns_sys.content + '\n\n' + _c -%}
      {%- endif -%}
    {%- endif -%}
  {%- endif -%}
{%- endfor -%}

{#- ===== SECTION 5: BUILD TOOLS LIST =====
     Normalise each tool to {"type":"function","function":{...}} format.
     Serialisation happens later at output time (avoids Markup + str escaping bugs).
-#}
{%- set _has_tools = tools is defined and tools -%}
{%- if _has_tools -%}
  {%- set ns_tb = namespace(list=[]) -%}
  {%- for tool in tools -%}
    {%- if tool.function is defined -%}
      {%- set ns_tb.list = ns_tb.list + [tool] -%}
    {%- else -%}
      {%- set ns_tb.list = ns_tb.list + [{"type": "function", "function": tool}] -%}
    {%- endif -%}
  {%- endfor -%}
{%- endif -%}

{#- ===== SECTION 6: OUTPUT SYSTEM TURN =====
     Each fragment output via its own {{ }} block so tojson Markup objects are
     never Python-concatenated with plain strings (would trigger HTML-escaping).
     User system content appears BEFORE the tools block (correct ordering).
     No default system prompt injected.
-#}
{%- if ns_sys.content or _has_tools -%}
  {{- '<|im_start|>system\n' -}}
  {%- if ns_sys.content -%}
    {{- ns_sys.content -}}
    {%- if _has_tools -%}{{- '\n\n' -}}{%- endif -%}
  {%- endif -%}
  {%- if _has_tools -%}
    {{- '# Tools\n\nYou may call one or more functions to assist with the user query.\n\nYou are provided with function signatures within <tools></tools> XML tags:\n<tools>\n' -}}
    {%- for tool in ns_tb.list -%}
      {{- tool | tojson -}}
      {%- if not loop.last -%}{{- '\n' -}}{%- endif -%}
    {%- endfor -%}
    {{- '\n</tools>\n\nFor each function call, return a json object with function name and arguments within <tool_call></tool_call> XML tags:\n<tool_call>\n{"name": <function-name>, "arguments": <args-json-object>}\n</tool_call>' -}}
  {%- endif -%}
  {{- '<|im_end|>\n' -}}
{%- endif -%}

{#- ===== SECTION 7: MAIN MESSAGE LOOP ===== -#}
{%- for message in messages -%}

  {#- 7a: System / Developer — already rendered above, skip -#}
  {%- if message.role == 'system' or message.role == 'developer' -%}

  {#- 7b: User messages -#}
  {%- elif message.role == 'user' -%}
    {%- set _uc = render_content(message.content | default(''), true) -%}
    {{- '<|im_start|>user\n' + _uc + '<|im_end|>\n' -}}

  {#- 7c: Assistant messages -#}
  {%- elif message.role == 'assistant' -%}
    {#- Safely extract content as string — guard against absent key (BUG-002 fix).
        Also support message.reasoning_content as an explicit think-block source
        (used by some frameworks that store thinking separately from content). -#}
    {%- if message.content is defined and message.content is string -%}
      {%- set _ac = message.content -%}
    {%- elif message.content is defined and message.content is iterable and message.content is not mapping -%}
      {%- set _ac = render_content(message.content) -%}
    {%- else -%}
      {%- set _ac = '' -%}
    {%- endif -%}

    {#- Reconstruct content from reasoning_content + content when the framework
        stores thinking separately (e.g. OpenAI-style reasoning_content field).
        Only apply when no think-block already present in _ac. -#}
    {%- if message.reasoning_content is defined and message.reasoning_content is string
        and message.reasoning_content | trim
        and '<think>' not in _ac -%}
      {%- set _ac = '<think>\n' + message.reasoning_content | trim + '\n</think>\n\n' + _ac -%}
    {%- endif -%}

    {#- Collect tool_calls if present -#}
    {%- set _tc = message.tool_calls if message.tool_calls is defined and message.tool_calls else [] -%}

    {#- Strip <tool_call> prefix from content when tool_calls also present
        (some frameworks duplicate the data in both fields) -#}
    {%- if _tc and '<tool_call>' in _ac -%}
      {%- set _ac = _ac.split('<tool_call>')[0] | trim -%}
    {%- endif -%}

    {#- Determine if this is the last-in-history assistant turn.
        When add_generation_prompt=False and this is the last message, think blocks
        must be preserved (and non-thinking prefill applied if needed).
        All other turns have their think blocks stripped. -#}
    {%- set _is_last_hist = loop.last and not (add_generation_prompt | default(false)) -%}

    {#- Think-block handling (BUG-001 fix + last-turn preservation):
        - Tool-call turns   : never strip (think block is part of the tool-call format)
        - Last-history turn : preserve; inject non-thinking prefill when absent
        - Historical turns  : strip using fuzzy end-tag matching to handle
                              </think>, </thinking>, </ think>, </think > variants -#}
    {%- if not _tc -%}
      {%- if _is_last_hist -%}
        {%- if '<think>' not in _ac and not ns.enable_thinking -%}
          {%- set _ac = '<think>\n\n</think>\n\n' + _ac -%}
        {%- endif -%}
      {%- else -%}
        {#- Fuzzy end-tag detection for historical turn stripping -#}
        {%- set _think_end = '' -%}
        {%- if '</think>' in _ac -%}
          {%- set _think_end = '</think>' -%}
        {%- elif '</thinking>' in _ac -%}
          {%- set _think_end = '</thinking>' -%}
        {%- elif '</ think>' in _ac -%}
          {%- set _think_end = '</ think>' -%}
        {%- elif '</think >' in _ac -%}
          {%- set _think_end = '</think >' -%}
        {%- endif -%}
        {%- if _think_end -%}
          {%- set _ac = _ac.split(_think_end)[-1].lstrip('\n') -%}
        {%- endif -%}
      {%- endif -%}
    {%- endif -%}

    {#- Emit the assistant turn -#}
    {{- '<|im_start|>assistant\n' -}}
    {%- if _ac -%}
      {{- _ac -}}
      {%- if _tc -%}{{- '\n' -}}{%- endif -%}
    {%- endif -%}

    {#- Render tool calls in Hermes format (BUG-006 fix: arguments as-is or tojson).
        Each value output via its own {{ }} block — never concatenated with plain strings
        in Python, which would trigger Markup HTML-escaping (BUG-003/markup fix). -#}
    {%- if _tc -%}
      {%- for tc in _tc -%}
        {{- '<tool_call>\n' -}}
        {{- '{"name": ' -}}{{- tc.function.name | tojson -}}
        {%- if tc.function.arguments is string -%}
          {{- ', "arguments": ' + tc.function.arguments -}}
        {%- else -%}
          {{- ', "arguments": ' -}}{{- tc.function.arguments | tojson -}}
        {%- endif -%}
        {{- '}' -}}
        {%- if not loop.last -%}
          {{- '\n</tool_call>\n' -}}
        {%- else -%}
          {{- '\n</tool_call>' -}}
        {%- endif -%}
      {%- endfor -%}
    {%- endif -%}
    {{- '<|im_end|>\n' -}}

  {#- 7d: Tool results — group consecutive tool messages into one user turn -#}
  {%- elif message.role == 'tool' -%}
    {%- set _prev_role = messages[loop.index0 - 1].role if loop.index0 > 0 else '' -%}
    {%- set _next_role = messages[loop.index0 + 1].role if not loop.last else '' -%}
    {%- if _prev_role != 'tool' -%}
      {{- '<|im_start|>user\n' -}}
    {%- endif -%}
    {{- '<tool_response>\n' -}}
    {{- message.content | default('') -}}
    {%- if _next_role == 'tool' -%}
      {{- '\n</tool_response>\n' -}}
    {%- else -%}
      {{- '\n</tool_response>' -}}
      {{- '<|im_end|>\n' -}}
    {%- endif -%}

  {#- 7e: Unknown role -#}
  {%- else -%}
    {{- raise_exception('Unexpected message role: ' + message.role) -}}
  {%- endif -%}

{%- endfor -%}

{#- ===== SECTION 8: GENERATION PROMPT =====
     enable_thinking=True  → open <think>\n prefill so llama.cpp reasoning-budget
                             and other inference engines can hook into the think-stream.
                             The model continues generating inside the open block.
     enable_thinking=False → exact non-thinking prefill: <think>\n\n</think>\n\n
                             (19-char closed block, BUG-005 fix)

     NOTE: The <think>\n opener is EPHEMERAL — it lives only in the generation
     prompt, never in chat history. Historical think-block stripping (BUG-001)
     is handled in Section 7c and is entirely unaffected by this change.
     No context poisoning risk.
-#}
{%- if add_generation_prompt -%}
  {{- '<|im_start|>assistant\n' -}}
  {%- if ns.enable_thinking -%}
    {{- '<think>\n' -}}
  {%- else -%}
    {{- '<think>\n\n</think>\n\n' -}}
  {%- endif -%}
{%- endif -%}